diff --git a/conservancy/static/js/supporter-page.js b/conservancy/static/js/supporter-page.js
index 3bee587b..d64ab864 100644
--- a/conservancy/static/js/supporter-page.js
+++ b/conservancy/static/js/supporter-page.js
@@ -36,33 +36,34 @@ if (window.location.hash === "#renew") {
     window.location.hash = "#renewal";
 }
 
-var $formCorrectionNeeded = $('#form-correction-needed');
+var formCorrectionNeeded = qs('#form-correction-needed');
 
 function init_sustainer_form_validation () {
     // Forms start in "invalid" form, with the errors shown, so that
     // non-Javascript users see the errors by default and know what they must
     // enter.  Now we hide those for JavaScript users:
-    $formCorrectionNeeded.addClass('hidden');
+    formCorrectionNeeded.classList.add('hidden');
 
-    $('form.supporter-form').each(function(index, form) {
+    qsa('form.supporter-form').forEach(function(form) {
         var $amountInput = $('input[type=number]', form).first();
+        var amountError = qs('.supporter-form-input .form-error', form);
         var $amountError = $('.form-error', $amountInput.parents('.supporter-form-input'));
 
         $amountError.on(NEW_AMOUNT_EVENT, function(event, amountData) {
             var isValid = amountData.newAmount >= amountData.minAmount;
             if (amountData.oldAmount === undefined) {
                 if (isValid) {
-                    $amountError.addClass('hidden');
+                    amountError.classList.add('hidden');
                 } else {
                     flipClass($amountInput[0], 'valid', 'invalid');
-                    $amountError.removeClass('hidden');
+                    amountError.classList.remove('hidden');
                 }
             } else if (isValid) {
                 flipClass($amountInput[0], 'invalid', 'valid');
-                $amountError.fadeOut();
+                hide(amountError);
             } else if (amountData.oldAmount >= amountData.minAmount) {
                 flipClass($amountInput[0], 'valid', 'invalid');
-                $amountError.fadeIn();
+                show(amountError);
             }
         });
 
@@ -75,12 +76,12 @@ function init_sustainer_form_validation () {
             amountInput.dataset.oldAmount = amountData.newAmount;
         }).trigger('focusout');
 
-        $(form).on('submit', function(event) {
+        form.addEventListener('submit', function(event) {
             var amountData = buildAmountData($amountInput[0]);
             if (amountData.newAmount >= amountData.minAmount) {
-                $formCorrectionNeeded.addClass('hidden');
+                formCorrectionNeeded.classList.add('hidden');
             } else {
-                $formCorrectionNeeded.removeClass('hidden')
+                formCorrectionNeeded.classList.remove('hidden')
                     .css("font-weight", "bold").css("font-size", "150%");
                 event.preventDefault();
             }
@@ -95,7 +96,7 @@ function init_sustainer_type_switching () {
         $selectedLink.addClass("supporter-type-selector-selected");
         $(".supporter-type-selection").hide();
         $(event.target.hash).show();
-        $formCorrectionNeeded.addClass('hidden');
+        formCorrectionNeeded.classList.add('hidden');
         return false;
     };
     $(".supporter-type-selector a").bind("click", selectSupportType);